There are many applications for a motor operating on a pressurized fluid. That fluid may, for example, be air, natural gas, carbon dioxide or a vaporizable liquid in an Organic Rankine Cycle system.
Particularly suited for many such applications is the, so called, “push-push” radial reciprocating motor. This type of motor has a set of two opposed cylinders with a crankshaft midway between the cylinders. Pistons in the cylinders are connected to the crankshaft by a common connecting rod having a Scotch yoke engaging the crank pin. A valving arrangement driven by the crankshaft directs pressurized fluid to the top of one piston and to the bottom of the other during a half revolution of the crankshaft. During the succeeding half revolution of the crankshaft pressurized fluid is directed to the top of the other piston and the bottom of the one piston. Thus, the crankshaft is propelled throughout each revolution creating a powerful torque.
U.S. Pat. No. 4,106,391 granted Aug. 15, 1978 to Roland T. Wheeler for “Motor” discloses a four cylinder radial push-push motor. That motor employs a fairly complex valve actuating mechanism including linkages between the valves for one set of cylinders and the Scotch yoke of the other set of cylinders.
There continues to be a need for a simplified and reliable push-push motor.